High Quality Content by WIKIPEDIA articles! The Ford Mansion is a mid-18th century mature version of the classical American architecture that was built by Jacob Ford, Jr. in 1774. It was acquired by the Washington Association of New Jersey in 1873. Today, it is owned by National Park Service. The Georgian styled mansion is known for being George Washington’s headquarters from December 1779 to June 1780.. The mansion is located in Morristown, New Jersey.